Date Duration Calculator

The date duration calculator measures the length of time between two dates and presents it as a duration — in days, in whole weeks plus days, and as an inclusive count. Choose the two dates and the duration appears instantly.

Thinking in terms of duration is natural for anything that spans a period: how long a project ran, the length of a stay or a trip, the gap between two anniversaries, or the time between a start and a finish. Rather than a single raw number, seeing the span expressed as weeks and days often makes it easier to grasp — "six weeks and two days" lands more clearly than "forty-four days".

The calculator shows the plain day count, which is the number of nights in the span, and an inclusive count that includes both the first and last day for when every calendar day matters. The week breakdown sits alongside them. Dates entered in either order are handled gracefully, with a note if the range is reversed.

All calculation is timezone-safe and runs privately in your browser, so the same two dates always give the same duration, and nothing you enter is sent anywhere.

To use it, pick both dates and press Count the days. If you specifically want the count of days between two dates framed as a difference, the days between dates calculator is its companion, and the working days calculator gives the duration in business days only.

Duration in days is the difference between the two dates, calculated at UTC midnight for timezone safety. Weeks are the whole number of seven-day blocks within that span, with any remaining days shown separately; the inclusive figure adds one to count both endpoints.